Zabbix - Track, record, alert and visualize performance and availability of IT resources
OneSignal - Customer engagement platform used by over 1 million developers and marketers; the fastest and most reliable way to send mobile and web push notifications, in-app messages, emails, and SMS.
Datadog - See metrics from all of your apps, tools & services in one place with Datadog's cloud monitoring as a service solution. Try it for free.
Firebase - Firebase is a cloud service designed to power real-time, collaborative applications for mobile and web.
Nagios - Complete monitoring and alerting for servers, switches, applications, and services
Brevo - Innovative online Email Marketing solution to manage your contacts, create & send your newsletters and track your results. More than 80 000 clients. Best prices and attractive features.